Process for improving the value of cakes of vegetable origin,notably to obtain proteins

ABSTRACT

A PROCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE ORIGIN IS DESCRIBED. THE CRUDE CAKES ARE MACERATED IN AN AQUEOUS MEDIUM WITH STRAINS OF MICROORGANISMS NOTABLY THE YEAST GEOTRICHUM CANDIDUM. THE CAKES ARE THUS FREED FROM THE SULPHUR-CONTAINING IMPURITIES AND AFLATOXINS WHICH CONTAMINATE THEM AND LINIT THEIR USE AT PRESENT. THE CAKES OBTAINED HAVE AN IMPROVED NITRITIVE VALUE. NEW, PURE PROTEINS CAN BE ISOLATED FROM THE MACERATION LIQUIDS BY PRECIPITATION TO THE ISOLECTRIC PH OR IN THE PRESENCE OF SALINE SOLUTION.

April 9, 197

Filed March 15, 1971 T. J. sTARoN 3,803,328

PROCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE ORIGIN, NOTABLY TO OBTAIN PROTEINS 6 Sheets-Sheet 1 i (\l V EN TOR 'T AD LE LFOEEFH 5T RUN April 9, 1974 v J. STARQN PROCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE.

' ORIGIN, NOTABLY TO OBTAIN PROTEINS Filed March 15. 1971 6 Sheets-Sheet z ATTURN E Y April 9, 1974 j STARON 3,803,328

PROCESS FOR IMPROVING THE VALUE OF CAKES 0F VEGETABLE ORIGIN, NOTABLY TO OBTAIN PROTEINS Filed March 15. 1971 6 Sheets-Sheet 15 50 Heures THAD'ZE 1T0$LPH 1mm:

ATTOR Nay H d r T. J. STARON 3,3 8 PRQCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE ORIGIN, NOTABLY TO OBTAIN PROTEINS 6 Sheets-Sheet 4 k 82 Bt [Gas rMvEAH'OK:

1' PH JTARQN THADEE To;

ATTORNEY April 9, 1974 T STARQN 3,803,328

PROCESS FOR IMPROVING THE VALUEOE CAKES OF VEGETABLE ORIGIN, NOTABLY TO OBTAIN PROTEINS Filed March 15. 1971 6 Sheets-Sheet 5 mvcw-roa L ---..,4 DEE T05 5 PH .STARG N ATTc: NEY

Apnl 9, 1974 STARQN 3,803,328

PROCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE ORIGIN, NOTABLY TO OBTAIN PROTEINS Filed March 15. 1971 6 Sheets-Sheet 6 IlllllJlLA INVEMT'LJR' United States Patent 3,803,328 PROCESS FOR IMPROVING THE VALUE OF CAKES OF VEGETABLE ORIGIN, N OTABLY TO OBTAIN PROTEINS Thadee Joseph Staron, Noisy-le-Roi, Yvelines, France, assignor to Etablissement Public: Institut National de la Recherche Agronomique, Paris, France Filed Mar. 15, 1971, Ser. No. 124,132 Int. Cl. A231 N US. Cl. 426-44 14 Claims ABSTRACT OF THE DISCLOSURE A process for improving the value of cakes of vegetable origin is described. The crude cakes are macerated in an aqueous medium with strains of microorganisms, notably the yeast Geotrichum candiaum. The cakes are thus freed from the sulphur-containing impurities and afiatoxins which contaminate them and limit their use at present. The cakes obtained have an improved nutritive value. New, pure proteins can be isolated from the maceration liquids by precipitation to the isoelectric pH or in the presence of saline solution.

The invention relates to the treatment of cakes made from seeds of vegetable origin. It notably relates to a process permitting such cakes to be detoxicated and improving their value by biological means notably to obtain proteins.

Numerous vegetable cakes are available at present, but their potential nutritive value is badly exploited. Furthermore, in certain cases, contaminants, particularly sulpuhr containing products, such as isothiocyanates, as well as aflatoxins, pollute cakes, such as colza and groundnut cakes. It is thus known that the presence of sulphur-containing products, and notably thioglycosides in colza cakes is at the origin of numerous physiological disorders observed in animals fed with said cakes. The bad effects, particularly the carcinogenic effects, of aflatoxins found in groundnut cakes and which are heterocyclic compounds excreted by fungi (Penicillium aspergillus) are also known.

Among the processes which have already been proposed to remove sulphur containing products from colza cakes may be mentioned the techniqueknown as toasting, distillation, steam stripping, extraction with solvents and treatment with salts of heavy metals, but none of these processes has been shown to be really effective. The use of groundnut cakes poses the same feeding problems as that of colza cake when they are polluted by afiatoxins. Moreover, the protein balance of many cakes made from vegetable seeds is unsatisfactory. In particular; the nitrogen efiiciency of the proteins of cakes, such as soya cakes, is not always sufiicient to render them fit for consumption by animals, and, a fortiori, by man.

The object of the invention is a process for treating cakes made from vegetable seeds which eliminates the drawbacks of the prior art.

The object of the invention is, thus, a process for detoxicating such cakes by biological means.

Another object of the invention is a process for improving the nutritive efficiency of such cakes by means of biological treatment.

Another object of the invention is the cakes obtained by such a process.

A further object of the invention is the new proteins obtained from said cakes by biological means, the said proteins being pure and being suited to human and animal feeding.

Generally speaking, the object of the invention is, therefore, a process for treating cakes made from vegetable seeds in which the said cakes are subjected, under conditions of maceration, to the action of at least one microorganism selected from bacteria, yeasts and fungi.

During the work leading up to the present invention, qualitative trials were undertaken on a large number of cakes made from vegetable seeds and on more than a thousand microorganisms. Up to the present, the most satisfactory results for operation on an industrial scale have been obtained with a yeast belonging to the species Geotrichum candidum. This microorganism will be described in greater detail in the following.

From a specific point of view, which is preferred, the object of the invention is, therefore, a process for treating cakes made of vegetable seeds in which the said cakes are subjected, under maceration conditions, to the action of the yeast Geotrichum candidum.

The cakes to which the process of the invention can be applied are made from seeds of any vegetable origin. Colza, rape, groundnut, sunflower, soya, sesame, castor oil, cotton vinia sinensis, broad bean (Fabzz vulgaris) and other vegetable seeds can, notably be mentioned.

It will be noted that the process of the invention is ap plied to cakes as they are available on the market. It is, therefore, necessary to stress this difference from certain prior fermentation techniques which were used on diluted juices or liquors obtained from vegetable seeds, such as groundnut. The invention, on the contrary, suggests a maceration process applied to crude cake.

Within the meaning of the present description, the words maceration conditions relates to a treatment consisting in placing cake in intimate contact with strains of the selected microorganism, the said treatment being carried out in an aqueous medium.

The usual macreation conditions imply a temperature slightly higher than ordinary temperature, in the range of 30 to 45 C. for example. With Geotrichum candz'dum the best results are obtained with maceration temperatures in the range of 37 to 40 C.

The pH of the maceration medium varies during the operation, but it generally remains between about 4 and 6.5. The pH is at its highest value at the start and it decreases during the treatment.

The length of treatment varies with the temperature, but it also depends on the results desired and other factors, such as the volume of the soaking tanks. With Geotrichum candidum, for example, sulphur containing products are completely eliminated in between 30 and 40 h. at 30 C., and this length of time falls below 30 h. if the operation is carried out under the same conditions, but at 37 to 40 C. To obtain total extraction of cake proteins and to isolate them as pure proteins, the treatment should be carried out under the same temperature for a period of about 60-90 h.

Maceration is carried out under stationary or stirred conditions with or without ventilation.

Another advantageous characteristic of the invention is that the maceration does not necessitate preliminary sterilization. Contacting of the microorganism culture and the vegetable cake is thus very easy to effect.

After maceration, the entire product is atomized, or the treated lump of cake is recovered by being separated from the maceration liquids. The value of the lump can then be-improved to be sold in powdered form. The maceration liquids are treated consecutively to isolate therefrom the pure proteins which have been rendered soluble during maceration. The protein fractions are isolated by isoelectric pH precipitation or by the addition of aqueous solutions of mineral salts of variable concentration, such as ammonium sulphate or by solvents (ethanol, methanol).

The invention will now be illustrated by the detailed description which follows:

I. Characteristics of the microorganism used (Geotrichum candidum) (l) Morphology and biology-Seen under the microscope, the myceliurn is white, branched and with frequent tein, pyrimidine, purine, puric nitrogen). However, puric I bases provided the best yields of proteins.

(2) Culture medium and conditions.--The strain is preserved on a solid Sauton medium.

Starting ferments for fermentation are obtained on a culture medium preferably consisting of:

(a) An inorganic solution of pH 6.8 (KH PQgl g.; MgSO 7H O:0.5 g.; KCl:0.2 g.; CaCl :0.2 g.; FeSO 7H O:0.03 g.; ZnSO 7H O:0.01 g.; CuSO 51-1 022 mg.; distilled water q.s.p. 100 ml.);

(b) Glucose 35 g./l.;

(c) Uric acid 5 g./l. or urea 4 g./l.

This medium is divided betwen 500 ml. erlenmeyer flasks in amounts of 100 ml. per erlenmeyer flask and then sterilized for 15 min. at 110 C.

Seeding is carried out in a sterile manner with an aqueour suspension of a 5-day old culture of Geolrichum candidum obtained on a Sauton medium.

Culturing is carried out on a rotating stirrer (130 revolutions/min.) at 30 C.; it lasts for 48 h.

Carried out in a fermentor, culturing is usually finished in about 20 h.

II. Testing methods Freeing of 5-vinylthiooxazolidone, abbreviated to VTO, selected as the compound representative of thioglycosidcs in the macerating liquid and the residual content of this substance in the insoluble cake, are tested as follows:

(a) Obtaining an enzymatic preparation of myrosinase. It has been shown that white mustard flour with the oil removed gives results comparable with the myrosinase solution. Consequently the said flour is used for practical requirements and in trials. This characteristic is illustrated in FIG. 1 which is a graph obtained with a colza cake showing the absorption curve of VTO (solid lines) as well as the absorption curve of mustard flour (dotted lines), the optical density being given in ordinates and the wave length A in nm. being given in abscissa.

The seeds of white mustard trialba are finely ground and their oil is removed three times over by 5 volumes of petroleum ether, dried at laboratory temperature and stored in a freezer at 20 C.

(b) Enzymatic reaction. In a 500 ml. Erlenmeyer flask, 2 g. of the cake to be analyzed and 0.2 g. of the mustard with the oil removed are weighed, then 100 ml. of phosphate buffer of pH 7 (Na HPO l2H O at 23.08 g./l =400 ml.; KH PO at 9.07 g./l=600 ml. are added. It is incubated with stirring at 30 C. for 2 h.

(c) Extraction and determination of VTO. The enzymatic reaction being ended, the solution is filtered through paper; 1 ml. of it is extracted twice over with 10 ml. sulphuric ether. The ethereal fractions are combined, made up to 25 ml. filtered on cotton wool and determined with a spectrophotometer (peak of the VTO at 248 nm.).

The absorption is measured at 225, 248 and 265 nm. and the corrected optical density is calculated by subtracting the mean of the values at 225 and 265 from the value at 248 nm. The difference obtained is inscribed on the Wetter standard curve (FIG. 2) to obtain the VTO content X in meg/ml.

The VTO content in g. per 100 g. of cake is determined according to the following equation:

wherein M is the mass of the trial sample in g.

FIG. 2 shows the Wetter standard curve which is known in this technique. The straight line of the graph represents the values of the optical density shown in ordinates as a function of the values of the concentration of VTO, expressed in ug/ml. and shown in abscissa.

EXAMPLE I This very complete example relates to colza cake.

(A) Maceration method and results obtained Maceration of the colza cake was carried out in a 40 1. pilot fermenter according to the following formulation:

Colza cake kg..- 6 Geotrichum candidum culture l 5 Tap water l 19 Starting pH==6.4; pH at extraction=4. This lowering of the pH is essentially due to the freeing of proteins in the culture liquids. FIG. 3 is a graph in ordinates on which is shown, on the one hand, the pH and, on the other, the amount of proteins in g./l. in the maceration supernatant, as a function of the duration of maceration shown in abscissa (hours). The upper curve shows the variation of the pH during maceration and the lower curve shows the freeing of proteins from the cake into the maceration liquid.

Culturing is carried out with slow stirring, or by a stationary technique, for 30 to 60 h. at 37 C. without preliminary sterilization. Indeed, preliminary trials have shown that under the conditions described no contamination has ever occurred. Furthermore, stirring the medium and ventilation do not appear to be necessary when small amounts are macerated.

Test portions permit the freeing of VTO in the maceration liquids and its progressive breakdown to be checked. FIG. 4 is a graph showing the freeing and breakdown of the VTO of colza cake due to the action of Geotrichum candidum. The amount of VTO is given in ordinates and is expressed in g./ 100 g. of colza cake. The maceration time, expressed in hours, is given in abscissa. Curve (1) shows the results obtained at a temperature of 37 C. and curve (2) corresponds to the results obtained at 27 C. The increase in temperature is seen to have a surprising effect. At 27 C., hydrolysis of thioglycosides occurs in a first time and it is only after 35 h. culturing that isothiocyanates breakdown starts, and they are only completely destroyed after h. maceration. At 37 C., on the other hand, hydrolysis of thioglycosides and breakdown of the isothiocyanates formed occur simultaneously.

During maceration, the Geotrichum candidum progressively solubilizes the colza cake proteins. Thus, when maceration is carried out for 60 to 80 h. at 37 C., of the proteins are dissolved. During the first 30 h. there are freed: a heteroprotein toxic to the mouse (protein a) and a protein containing large amounts of glutamic acid, proline, lysine and sulphurized amino acids (protein B). After 35 h. protein a. is observed to disappear and soluble fractions are freed with an amino acid composition very similar to that of total colza cake (see table below).

Fractions so obtained can easily be leached out by conventional chemical methods and contain between 65 and 80% proteins.

(B) Recovery and modes of treatment of macerated colza cake Macerated cake was treated in various ways:

(a) Recovery of the entire macerated mass and evaporation of water by atomization.

(b) Isolation of the insoluble fraction by centrifugation and drying.

(0) Separation of the soluble fraction and drying.

(d) Fractionation of the soluble fraction by SO (NH Operating under these conditions it is possible to distinguish the following fractions:

( 1) Total macerated colza cake (2) Macerated colza cake, insoluble fraction (3) Macerated colza cake total soluble fraction 6 Table I above shows that maceration with Geotrichum candidum causes colza cake to become richer in most of the indispensable amino acids, which explains its good protein efliciency.

As has been mentioned, protein B can be isolated from hf tt' 1"d'thfll 4 Protein which reci itates b the addition of 207 t 6 am 5 m 6 Owmg mannergOoNH 2 z perpvolumey o 20% (w./v.) of (NH SO 1s added to the fermenta- Protein B which precipitates with 40% SOMNH)2 tion liquids; the precipitate obtained 1s removed; 20% 504N114) zby Weight Per volume (w./v.) of (NH. SO is added to the supernatant and (C) Com arative stud of the amino acid com osition 10 Elm sea-Hid pr-eclpitat-e collecteci 1?}, centrifugation; it of th proteins g arious fraction emailed 1S solubilized m a mmunum of distilled water, dialized ep v S and freeze-dried. About 17 g. of protein per liter of Proteins are determined after mineralization by the maceration liquid is thus obtained. l h s The amino acids are h y With a This fraction is water soluble, it contains 100% pro- Techhlcoll y n after hydfolysls of the P tein, it has an ultraviolet absorption spectrum (peak at f a sealed tube HQ 6 for 24 and at 225 m it is homogeneous with electrophoresis and 32 dgtermufed f i i i migrates towards the anode, its isoelectric pH is 12.2.

9 zz I z gi g 2?; zg iizzz z z 8; With hydrochloric hydrolysis, this protein frees all the not damage the composition of proteins in the colza cake i zgg i ii $332 ig sg g z charactenzed by hlgh during maceration; on the other hand, it progressively g p frees protein fractions with a variable amino acid com- This molecule has the property 9 preclpltatmg certam position natural polymers such as polyuromdes and nucleic acids.

Protein 8, rich in glutamic acid, proline, lysine, histidine and sulphurized amino acids, represents of the total 25 (D) Numtlonal exPenmem on the mouse proteins.

The cellulose content increases in the insoluble mm Tests on the food value of macerated cake were carried tion during maceration because this element is not atout on the f" tacked, but it can, however, easily be removed 180 female Imce were divided into 6 lots of mice. During maceration, the cake is found to lose about 30 The control feed was that commonly used. In the other 10% of its weight; this occurs essentially to the detriment 5 feeds tested, the groundnut and y cake were of carbohydrates. placed by the colza cakes to be experimented.

TABLE I Percent by dry weight Macerated Total Macerated colza cake, Colza atomized colza cake total cake macerated insoluble soluble control colza cake fraction fraction Protein 5 Protein content 35. 3 45. 2 Variable 64 10 Aspartic acid 7. 0 5. 9 7. 0 7. 0 2.4 Threonine 4.3 4.5 4.5 4.0 3.0 Serine 4. a 4. 2 3. s 4.4 a. 2 Glutamic acid- 18.3 18. 7 17. 0 19. 2 26. 0 roline 7. 4 7.1 7. a 7. 2 9. 2 Glycine 5. 2 5. 2 5. s 5. 2 4.1 Alanine 4. 2 4. 9 5. 0 5. 2 3. 8 Valine- 4. 7 4. 9 5.1 4. s a. 9 Cystine 2. e 2. 7 2. a 3. 2 4. s Methionin 1. 9 2. o 1. s 2.1 2. 4 Isoleucine 4. 6 4. 5 4. 6 4. 3 3. 2 Leueine 7. 0 6. 9 7. l. 7. 3 6. 1 Tyrosine 2. 5 2. e 3. 1 2. 9 1. 4 Phenylalanine 4.2 4.0 4.1 3.9 2.8 Ammonia/liquor.- 1. 8 1. 7 1.6 1. 6 2. 3 Lysine 5. 3 5. 6 5.1 6.1 6.8 Histidine 2. 7 2. 9 3. o a. 2 a. 5 Argininenn 6. 5 6. 6 6.8 6. e 5.6 Tryptophan 1 2 0. 9

Cellulose 14 17 Variable 2 0 Table II hereinbelow gives the compositions of the feeds used.

TABLE II Feed number Constituents, percent:

Bar ey Maize Groundnut cake. Soya calm Colza cake Polish colza cake Total atomized maeerated colza cake Macerated colza cake plus reineorporated CL protein and tree VTO Macerated colza cake total soluble fraction Powdered mil k prepared by atomization Mineral and vitamin additions Percent of total proteins-.

P muocoow-oo S p H :neeooomoooooom-w {3 Z 9 H u: rommoaoow-oooooomwo:

' P toaotwoooooooo P a: Name:

Thioglycosides content (expressed in VTO), mg./g

Free VTO content, mgJQ Weight gain per mouse in g 1 Control.

An increase in proteins was found in all the organs oi lot No. 5, except in muscle where their level is lower. It is interesting to note that lots 2 and 3 occupy intermediate positions.

The total phosphorous contents in the organs of lot No. 5 were very low. A decrease in this element was also observed in lots 2 and 3; notably in the bones.

Free hepatic glucose was very much increased in mice of lots No. 2, 3 and 5. This phenomenon could be caused by an inhibition of phosphorylation.

Results of analyses of the mice of lot 5 bis show that the disturbances observed in lot No. 5 are rapidly reversible when the diet is altered.

Analyses of lot No. 6 indicate that macerated colza cake with the cellulose removed is an excellent foodstuff for mice.

(F) Conclusions The preceding results show clearly that the subjecting colza cakes to maceration in the presence of a stain of Geotrichum candidum the food value of these cakes is improved.

Yeast acts in at least two ways: on the one hand, hydrolysis of thioglycosides with breakdown of the isothiocyanates formed is observed; on the other, there is freeing, followed by destruction, of toxic heteroprotein compounds.

The fraction precipitating at 20% of S (NH (protein 0:) administered to the mouse by mouth stops its growth at a dose of 20 mg./ kg.

By continuing fermentation, complete solubilization of colza proteins is observed, which can easily be leached out by conventional chemical methods. The fractions thus obtained contain between 65 and 80% proteins and are suitable for texturization.

The overall composition of these fractions in amino acids remains substantially the same as in the original cake. It is, however, possible to isolate a protein (protein 5) which accounts for 25% of the total proteins and which possesses a very special structure and properties.

Nutritional experiments carried out on the mouse showed that colza cake is not toxic to the mouse in as far as can be ascertained by weight measurements. However, by the many analyses carried out on organs, major disturbances are found in the amino acids, free glucose, proteins and phosphates in the case of mice fed with colza cake containing large amounts of thioglycosides, and Polish cake which does not contain any.

In short, the results of detailed experiments given hereinabove clearly show that maceration of colza cake with Geotrichum candidum markedly improves the balance of amino acids and the food value of colza cake, in the case of mice, for instance.

EXAMPLE 2 TABLE IV The evolution of the breakdown of atlatoxlns in groundnut cakes macerated with Geotrichum candidum Aflatoxins (meg/kg. of cake) Lot No. 1 Lot No. 2 Lot No. 3

Maceration time (h 10 The results given above in Table IV show that toxic compounds disappear completely after 36 h. of maceration. The balance of amino acids and the nutritive value of groundnut cakes are, therefore, markedly improved by the treatment of the invention.

EXAMPLE 3 Soya cakes were subjected to maceration conditions with Geotrichum candidum in order to improve the nitrogen efiiciency of soya proteins. The results obtained were studied in nutritional trials on the mouse.

Two lots of 40 female mice were formed. The control lot recei'ved feed No. 1 defined in Table II of Example 1; the second lot received the same feed in which the traditional soya cake was replaced by macerated soya cake. The results are given in FIG. 6.

FIG. 6 is a graph on which the weight increase "of the mice, expressed in g., is shown in ordinates as a function of time expressed in weeks. The upper curve corresponds to feeding with soya cake macerated according to the invention, whereas the lower curve corresponds to normal feeding (feed No. 1). The figure clearly showsthat the growth of mice is better with the macerated soya cake.

The amino acid composition of the proteins appears to differ very little in the two batches of soya, so it would seem that the greater nitrogen efficiency of the macerated cake is due to the breakdown of the thioglycosides and a profound modification of the carbohydrates, certain constituents of which act as antimetaboles and enzyme inhi bitors.

The invention has only been illustrated by the preceding, nonlimiting examples. It should, indeed, be noted that the process of treatment by biological means is applicable to cakes of any vegetable origin.

What is claimed is:

1. Process for removing toxic substances from cake obtained from vegetable seeds comprising contacting the cakes in maceration condition in an aqueous medium with the microorganism Geotrichum candidum at a temperature and for a time suflicient for removal of the toxic substances from the cake and thereafter separating the cake from the aqueous medium.

2. Process according to claim 1, the temperature being about 30 to 45 C.

3. Process according to claim 1, the pH during said contacting being about 4-6.5.

4. Process according to claim 2, the pH during said contacting being about 4-6.5.

5. Process according to claim 1, the temperature being about 30 C., the time being about 30-40 hours.

6. The process of claim 1 wherein the cakes are selected from cakes made of colza and rape, groundnut, sunflower, soya, sesame, castor oil, cotton, vinia sinensis, and broad bean (F aba vulgaris) 7. The process of claim 10 wherein the temperature of treatment is in the range of about 30 to 45 C.

8. The process of claim 1 in which the contacting temperature is in the range of about 37 to 40 C.

9. The process of claim 1 in which the pH of the treatment medium varies between about 4 to 6.5.

10. The process of claim 1 in which the treatment is continued until the sulphur-containing impurities contaminating the starting cake are eliminated.

11. The process of claim 1 in which the treatment is continued until the extraction of proteins of the starting cakes and substantially complete solubilization of said proteins in the treatment medium occurs.

12. The process of claim 1 which comprises the additional stage of isolation of pure proteins solubilized in the said separated aqueous medium by the addition of aqueous 1 1 solutions of inorganic salts or of organic solvents, and separation of the precipitated protein fractions.

13. The process of claim 12 in which the inorganic salt is ammonium sulphate.

14. The process of claim 12 in which the treated cake is colza cake and where aqueous solutions of ammonium sulphate at 20% and 40% are used successively in order to isolate the protein fractions.

12 References Cited UNITED STATES PATENTS 2,960,408 11/1960 Geister et a1. 99--9 2,516,128 7/1950 'Breton et a]. 195-4 3,635,726 1/1972 Sair 99-17 2,607,768 8/1952 McCready 260-1235 LIONEL M. SHAPIRO, Primary Examiner 1 UNITED OFFE I CERTIFICATE OF CORRECTION Potent No. 39 3 Mad pril 9, 1974 invoncoflo) Thadee Q ph Staron I v I V w v v C It is certified thacerror appears in the above-identified patent one] that laid Lcttoro Potent ore hereby corrected as ahoyn below:

Col. 3 line chng "100 m1..[" to --1000,m1.-.-

Col. 5, 9, cancel, S0 (NH Col. 5, line 17, change "tryfiophan" to tryp'tophannen--.

' Table 1 the fir sfentr'y, a fter "Ptotein content" insert -"-in Z. by dry weight Table I, the first entry, last column (Protein I5),

change."1 0"' to +100--.

Signod and sealod this 28th day of Jonnary 1975.

(SEAL) Attest:

McCOY M. GIBS'QN' JR. c. MARSHALL DANN Attesting Officer Commissioner of Patents 

